SQL Query Help

I have to qurery to get the distict value of coulmn 2 where coumn3 has value X. For example B2 has a value 'Q' in column2 then it should not be selected.All B3 has value X then it should be selected.
Any help will be appriciated.


Coloumn1 Coloumn2 Coloumn3
1 B1 X
2 B1 X
3 B2 Q
4 B2 X
5 B2 X
6 B3 X
7 B3 X
8 B3 X
9 B4 Q
10 B4 Q
11 B5 X
12 B6 X
13 B6 X

Result
Coloumn2
B1
B3
B5
B6